TOP257YN

AC DC Converters, Offline Switchers Overview

The TOP257YN is an enhanced EcoSmart integrated off-line switcher from Power Integrations. It incorporates a 700 V power MOSFET, high voltage switched current source, PWM control, oscillator, thermal shutdown circuit, and fault protection on a monolithic device. The component operates at a switching frequency of 132 kHz and supports a maximum duty cycle of 83%. It features a TO-220-7C package with through-hole mounting. The device is designed for universal input voltages ranging from 85 VAC to 265 VAC.

AC DC Converters, Offline Switchers Feature Summary

• Multi-mode operation maximizes efficiency across all load conditions
• Output overvoltage protection is user programmable for latching or non-latching shutdown
• Line undervoltage detection prevents turn-off glitches during operation
• Frequency jittering reduces electromagnetic interference filter costs

AC DC Converters, Offline Switchers Applications

• Universal input AC/DC adapters
• Monitor and display power supplies
• General purpose offline power conversion
• Battery chargers requiring low standby power

AC DC Converters, Offline Switchers Procurement Notes

Verify the specific suffix 'YN' corresponds to the TO-220-7C package variant when sourcing. Confirm that the application design accounts for the 132 kHz switching frequency requirements. Ensure thermal management strategies align with the junction-to-case thermal impedance specifications provided in the official datasheet for the intended power level.

AC DC Converters, Offline Switchers Selection Notes

Select this component for designs requiring high efficiency at both light and full loads due to its multi-mode operation. The TO-220-7C package allows for simple mounting using a clip, which aids in low-cost manufacturing processes. Consider the extended creepage distance from the DRAIN pin to adjacent pins when determining board layout spacing requirements.

AC DC Converters, Offline Switchers Part Context

This part belongs to the TOPSwitch-HX family, which integrates power switching and control functions into a single monolithic chip. The TOP257 model specifically targets applications needing up to 48 W output power at 230 VAC. It represents an evolution in integrated switcher technology focusing on system cost reduction and design flexibility.

AC DC Converters, Offline Switchers Replacement Considerations

TOP257PN

AC DC Converters, Offline Switchers FAQ

Is the output overvoltage protection fixed or adjustable?

The output overvoltage protection is user programmable, allowing selection between latching and non-latching shutdown modes with fast AC reset.

What is the primary benefit of the 132 kHz switching frequency?

The 132 kHz frequency reduces transformer and power supply size compared to lower frequency alternatives.